The present invention relates to a disk drive apparatus capable of carrying out stable recording and reproduction by suppressing undesirable vibration and noise caused by an imbalance on a disk used as a recording medium.
In recent years, in disk drive apparatuses for recording/reproducing data, high-speed disk rotation is being advanced to improve data transfer rate. For example, in a CD-ROM disk drive apparatus, its rotation speed has increased from a conventional value of the order of 5000 rpm to 6000 rpm or more. This tendency is similarly shown not only in the half-height disk drive apparatuses for desktop computers but also the low-profile disk drive apparatuses for notebook computers.
However, there are various disks; some disks have a mass imbalance due to nonuniform thickness, and other disks have a mass imbalance due to the paper seal stuck thereto to indicate the contents recorded thereon. The amount of the mass imbalance of the disk reaches about 1 gcm in the case when the amount is large. When this kind of disk is rotated at high speed, an eccentric centrifugal force (an imbalance force) acts on the rotation center of the disk, thereby causing a problem wherein the vibration due to the imbalance force is transmitted to the whole of the device. The magnitude of this imbalance force increases in proportion to the square of rotation frequency (Hz) (rotation frequency is the revolutions per unit time (revolutions/sec) of a disk 501). For example, when increasing the rotation speed of a disk having a mass imbalance of 1 gcm by only about 10%, from 5400 rpm to 600 rpm, the imbalance force increases about 1.2 times, and the vibration also increases significantly.
When the mass of the disk is M (g), and when the distance from the center of the disk to the center of gravity of the disk is L (cm), the mass imbalance amount A (gcm) is represented by A=Mxc3x97L.
When this kind of unbalanced disk is rotated at high speed, noise occurs due to its vibration, the bearings of the spindle motor for rotating the disk are damaged, thereby causing a problem wherein stable recording and reproduction cannot be attained.
Furthermore, when this kind of disk drive apparatus is built in an apparatus such as a computer, the vibration is transmitted to other devices inside the apparatus, thereby also causing a problem of adversely affecting the devices.
For these reasons, to improve data transfer rate by rotating the disk at high speed, it is necessary to accomplish a task of suppressing undesirable vibration due to the mass imbalance of the disk.
An example of a conventional disk drive apparatus will be described below referring to the drawings.
FIG. 72 is a perspective view showing the main unit of the conventional disk drive apparatus. Referring to FIG. 72, a disk 1 is rotated by a spindle motor 2; and a head 3 reads data recorded on the disk 1 or writes data on the disk 1. A head drive mechanism 5, comprising a rack, a pinion and the like, converts the rotation motion of a head drive motor 4 into a linear motion, and transmits it to the head 3. The head 3 is configured so as to be moved in the radial direction of the disk 1 by this head drive mechanism 5. The spindle motor 2, the head drive motor 4 and the head drive mechanism 5 are mounted on a sub-base 6. Vibration and impact transmitted from outside the device to the sub-base 6 are dampened by insulators 7 (elastic bodies), and the sub-base 6 is mounted on a main base 8 via these insulators 7. The main unit of the disk drive apparatus shown in FIG. 72 is configured so as to be built on a computer or the like via a frame (not shown) installed in the main base 8.
FIG. 73 is a side sectional view showing the vicinity of the spindle motor 2 of the conventional disk drive apparatus. A turntable 110 is secured to the shaft 21 of the spindle motor 2 and rotatably supports the clamp area 11 of the disk 1. Inside the boss 14 formed on the turntable 110, a positioning ball 116 making contact with the corner portion of the clamp hole 12 of the disk 1 by virtue of a pressing means 113, such as a coil spring, is built in. In this way, the disk 1 is disposed at a predetermined position by the pressing operation of the positioning ball 116.
In the conventional disk drive apparatus configured as describe above, in the condition wherein the disk 1 is disposed and clamped on the turntable 110, by making the positioning ball 116 contact with the corner portion of the clamp hole 12, the disk 1 is aligned and held on the turntable 110 by the pressing force of the pressing means 113. The disk 1 held in this way is rotated integrally with the turntable 110 by the spindle motor 2.
However, in the conventional disk drive apparatus having the above-mentioned configuration, if the disk 1 having a mass imbalance due to nonuniform thickness, a seal, etc. stuck thereon is mounted and rotated at high speed, a centrifugal force (an imbalance force) F acts on the center of gravity G1 of the disk 1 shown in FIG. 73. The direction of the action rotates as the disk 1 rotates. This imbalance force F is transmitted to the sub-base 6 via the turntable 110 and the spindle motor 2; however, since the sub-base 6 is supported by the insulators 7 used as elastic bodies, it is whirled significantly by the imbalance force F while the insulators 7 are deformed. Since the magnitude of the imbalance force F is proportional to the product of the mass imbalance amount (represented by the unit of gcm) and the square of the rotation frequency, the vibration acceleration of the sub-base 6 increases drastically in close proportion to the square of the rotation frequency of the disk 1. As a result, such problems occur that noise was caused due to the resonance of the sub-base 6 itself and the head drive mechanism 5 mounted on the sub-base 6, and stable recording and reproduction became impossible due to significant vibration of the disk 1 and the head 3.
To cope with the above-mentioned problems, in the conventional disk drive apparatus, the spring constant of the insulators 7 was raised, or an elastic material, such as a leaf spring, was provided between the sub-base 6 and the main base 8 as countermeasures to suppress the vibration amplitude of the sub-base 6.
However, if the rigidity of the connection portion between the sub-base 6 and the main base 8 was raised in this way, when vibration and impact were applied reversely from outside the drive device to the disk drive apparatus, the vibration and impact were directly transmitted to the sub-base 6 on which the disk 1, the head 3 and the like were mounted, and stable recording and reproduction became impossible, thereby causing a problem of reducing the so-called vibration-resistant and impact-resistant characteristics.
Furthermore, the vibration of the sub-base 6 due to the imbalance force F was transmitted to the outside of the disk drive apparatus via the main base 8 and the like, thereby causing a problem of adversely affecting other devices in the computer in which this disk drive apparatus was built.
Moreover, a large side pressure was applied to the bearings of the spindle motor 2 by the imbalance force F, whereby the loss of the shaft torque increased, and the bearings were damaged, thereby to cause a problem of shortening the service life of the bearings.
In consideration of the above-mentioned problems, the present invention is intended to provide a disk drive apparatus capable of carrying out stable recording and reproduction even when an unbalanced disk is rotated at high speed, and also capable of carrying out high-rate transfer while having high reliability in preventing vibration and impact from outside the device.
In order to solve the above-mentioned problems, the disk drive apparatus of the present invention is a device wherein a balancer having a ring-shaped track portion accommodating balance members is provided so as to rotate integrally with a disk mounted on the disk drive apparatus; and concrete means thereof are described below.
A disk drive apparatus in accordance with the present invention comprises:
a balancer provided so as to be rotatable integrally with a mounted disk and having a ring-shaped track portion accommodating balance members, wherein
the balancer satisfies the relationship of:
hxe2x89xa7f2xc3x97|Axe2x88x92Z|,
when the total mass of the above-mentioned balance members is M [g], the distance to the center of gravity of the total of the above-mentioned balance members from the center axis of the above-mentioned ring-shaped track portion is T [cm], a balance amount Z [gcm] is represented by:
Z=Mxc3x97T,
when the maximum rotation frequency of the above-mentioned disk is f [Hz], the maximum of the mass imbalance amount of the above-mentioned disk is A [gcm], and a constant is h.
Therefore, in accordance with the disk drive apparatus of the present invention, even if the disk is rotated at high speed, vibration due to the mass imbalance of the disk can be suppressed securely, whereby it is possible to attain a disk drive apparatus capable of carrying out high-rate transfer.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a balancer provided so as to be rotatable integrally with a mounted disk and having a ring-shaped track portion accommodating spherical bodies, wherein
the balancer satisfies the relationship of:
hxe2x89xa7f2xc3x97|Axe2x88x92Z|,
when the radius of the above-mentioned spherical body is r [cm], the radius of the inner wall face of the outer periphery of the above-mentioned ring-shaped portion is S [cm], the number of the above-mentioned spherical bodies is n, the specific gravity of the above-mentioned spherical body is xcfx81, and a balance amount Z [gcm] is represented by:
Z=4/3xcfx80r2xcfx81(Sxe2x88x92r)2xc3x97sin[n sinxe2x88x921{r/(Sxe2x88x92r)}],
when the maximum rotation frequency of the above-mentioned disk is f [Hz], the maximum of the mass imbalance amount of the above-mentioned disk is A [gcm], and a constant is h.
Therefore, in accordance with the disk drive apparatus of the present invention, even if the disk is rotated at high speed, vibration due to the mass imbalance of the disk can be suppressed securely, whereby it is possible to attain a disk drive apparatus capable of carrying out high-rate transfer.
In a disk drive apparatus in accordance with the present invention, the above-mentioned constant h may be represented by:
h=fo2xc3x97Ao,
in the case when the maximum allowable rotation frequency wherein vibration becomes an allowable value or less is fo [Hz] at the time when a disk having a mass imbalance amount Ao [gcm] is rotated in a condition wherein the above-mentioned balance amount Z=0 [gcm].
Furthermore, in a disk drive apparatus in accordance with the present invention, it is preferable that the diameter of a disk to be mounted is 12 [cm] or less, and that the above-mentioned constant h is 8100.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a head for carrying out recording or reproduction on a mounted disk; and
a balancer provided so as to be rotatable integrally with the above-mentioned disk and having a ring-shaped track portion accommodating balance members, wherein
said balancer is disposed on the same side of the above-mentioned head with respect to the recording face of the above-mentioned disk used as a reference face.
Therefore, in accordance with the disk drive apparatus of the present invention, even if a mounted unbalanced disk is rotated at high speed, vibration can be suppressed sufficiently, whereby it is possible to attain a low-profile disk drive apparatus capable of carrying out high-rate transfer.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a head for carrying out recording or reproduction on a mounted disk; and a balancer provided so as to be rotatable integrally with the above-mentioned disk and having a ring-shaped track portion accommodating balance members, wherein
the distance from the outer wall face of the outer periphery of the above-mentioned ring-shaped track portion to the center axis of the above-mentioned ring-shaped track portion is smaller than the distance from the end face of the inner peripheral side of the head being positioned at the innermost track to the center axis of the above-mentioned ring-shaped track portion.
Therefore, in accordance with the disk drive apparatus of the present invention, even if a mounted unbalanced disk is rotated at high speed, vibration can be suppressed sufficiently, whereby it is possible to attain a low-profile disk drive apparatus capable of carrying out high-rate transfer.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a motor base to which a spindle motor for rotating a disk is secured;
a sub-base over which the above-mentioned motor base is installed via elastic bodies, and on which a head for carrying out recording or reproduction on the above-mentioned disk is provided movably in the radial direction of the above-mentioned disk; and
a balancer provided so as to be rotatable integrally with the above-mentioned disk and having a ring-shaped track portion accommodating balance members.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the disk can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation.
A disk drive apparatus in accordance with the present invention from another point of view is configured so that the above-mentioned disk is rotated at a frequency higher than the primary resonance frequency of the whirling vibration of the above-mentioned motor base due to the deformation of the above-mentioned elastic bodies.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the disk can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a balancer provided so as to be rotatable integrally with a mounted disk and having a ring-shaped track portion accommodating spherical bodies, wherein the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is inclined with respect to the center axis of the above-mentioned ring-shaped track portion.
Therefore, in accordance with the disk drive apparatus of the present invention, even when the mass imbalance amount of the mounted disk is very large, it is possible to attain a disk drive apparatus having a high vibration suppression effect and being capable of reducing-undesirable noise.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a balancer provided so as to be rotatable integrally with a mounted disk and having a ring-shaped track portion accommodating spherical bodies, wherein the sectional shape of the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is a wedge.
Therefore, in accordance with the disk drive apparatus of the present invention, vibration due to the mounted unbalanced disk can be suppressed, and undesirable noise caused from the balancer itself can be reduced.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a balancer provided so as to be rotatable integrally with a mounted disk and having a ring-shaped track portion accommodating spherical bodies, wherein the sectional shape of the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is a curve.
Therefore, in accordance with the disk drive apparatus of the present invention, even when a disk having a large mass imbalance is mounted, or even when a disk having a small mass imbalance is mounted, vibration can be suppressed securely, and undesirable noise can be reduced.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view is:
provided so as to be rotatable integrally with a mounted disk and has a ring-shaped track portion accommodating spherical bodies, wherein the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is inclined with respect to the center axis of the above-mentioned ring-shaped track portion.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view is:
provided so as to be rotatable integrally with amounted disk and has a ring-shaped track portion accommodating spherical bodies, wherein the sectional shape of the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is a wedge.
Therefore, in accordance with the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view is:
provided so as to be rotatable integrally with amounted disk and has a ring-shaped track portion accommodating spherical bodies, wherein the sectional shape of the inner wall face of the outer periphery of the above-mentioned ring-shaped track portion is a curve.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, even when a disk having a large mass imbalance is mounted, or even when a disk having a small mass imbalance is mounted, vibration can be suppressed securely, and undesirable noise caused from the balancer itself can be suppressed.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view is:
provided so as to be rotatable integrally with amounted disk and has a ring-shaped track portion accommodating balance members, wherein
the balancer satisfies the relationship of:
hxe2x89xa7f2xc3x97|Axe2x88x92Z|,
when the total mass of the above-mentioned balance members is M [g], the distance to the center of gravity of the total of the above-mentioned balance members from the center axis of the above-mentioned ring-shaped track portion is T [cm], a balance amount Z [gcm] is represented by:
Z=Mxc3x97T,
when the maximum rotation frequency of the above-mentioned disk is f [Hz], the maximum of the mass imbalance amount of the above-mentioned disk is A [gcm], and a constant is h.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, even if the disk is rotated at high speed, vibration due to the mass imbalance of the disk can be suppressed securely, whereby it is possible to attain a disk drive apparatus capable of carrying out high-rate transfer.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view is:
provided so as to be rotatable integrally with amounted disk and has a ring-shaped track portion accommodating spherical bodies, wherein
the balancer satisfies the relationship of:
hxe2x89xa7f2xc3x97|Axe2x88x92Z|,
when the radius of the above-mentioned spherical body is r [cm], the radius of the inner wall face of the outer periphery of the above-mentioned ring-shaped portion is S [cm], the number of the above-mentioned spherical bodies is n, the specific gravity of the above-mentioned spherical body is xcfx81, and a balance amount Z [gcm] is represented by:
Z=4/3xcfx80r2xcfx81(Sxe2x88x92r)2xc3x97sin[n sinxe2x88x921{r/(Sxe2x88x92r)}],
when the maximum rotation frequency of the above-mentioned disk is f [Hz], the maximum of the mass imbalance amount of the above-mentioned disk is A [gcm], and a constant is h.
In a balancer for a disk drive apparatus in accordance with the present invention, the above-mentioned constant h may be represented by:
h=fo2xc3x97Ao,
in the case when the maximum allowable rotation frequency wherein vibration becomes an allowable value or less is fo [Hz] at the time when a disk having amass imbalance amount Ao [gcm] is rotated in a condition wherein the above-mentioned balance amount Z=0 [gcm).
In a balancer for a disk drive apparatus in accordance with the present invention, it is preferable that the diameter of a disk to be mounted is 12 [cm] or less, and that the above-mentioned constant h is 8100.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, even if the disk is rotated at high speed, vibration due to the mass imbalance of the disk can be suppressed securely, whereby it is possible to attain a disk drive apparatus capable of carrying out high-rate transfer.
Furthermore, in order to attain the above-mentioned objects, the disk drive apparatus of the present invention is a device wherein a balancer having a ring-shaped track divided into plural tracks and balance members movable along the divided tracks respectively is provided so as to be rotatable integrally with a disk; and concrete means thereof are described below.
A disk drive apparatus in accordance with the present invention comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation without losing vibration-resistant and impact-resistant characteristics.
A disk drive apparatus in accordance with the present invention from another point of view comprises a balancer having division means for dividing a ring-shaped track into plural tracks, arc-shaped tracks formed by the above-mentioned division means, and balance members provided so as to be movable on the above-mentioned arc-shaped tracks.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation without losing vibration-resistant and impact-resistant characteristics.
In a disk drive apparatus in accordance with the present invention, the above-mentioned division means may be configured to absorb shock.
Therefore, in accordance with the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed.
In a disk drive apparatus in accordance with the present invention, in at least portions of the above-mentioned arc-shaped tracks, the distance from the rotation axis of a disk to at least one track increases in the rotation direction of the above-mentioned disk.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation without losing vibration-resistant and impact-resistant characteristics.
In a disk drive apparatus in accordance with the present invention, the above-mentioned division means may be configured to be held so as to be rotatable with respect to the ring-shaped tracks.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby stable recording or reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-speed rotation without losing vibration-resistant and impact-resistant characteristics.
In a disk drive apparatus in accordance with the present invention, the above-mentioned balance members may be formed of a magnetic material, and magnetic field generation means having magnetic poles may be disposed in the vicinity of the above-mentioned division means.
Therefore, in accordance with the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed regardless of the high speed or low speed of disk rotation.
In a disk drive apparatus in accordance with the present invention, the above-mentioned balance members may be formed of a magnetic material, magnetic field generation means having magnetic poles may be disposed in the vicinity of the above-mentioned division means, and shock-absorbing members may be provided in the above-mentioned ring-shaped tracks at positions opposite to the positions of the magnet poles of the above-mentioned magnetic field generation means.
Therefore, in accordance with the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed regardless of the high speed or low speed of disk rotation.
In a disk drive apparatus in accordance with the present invention, the above-mentioned balance members may be formed of a magnetic material, magnetic field generation means for magnetically attracting the above-mentioned balance members may be provided, and the connection portions between the above-mentioned division means and the above-mentioned ring-shaped tracks may be formed of curves.
Therefore, in accordance with the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed regardless of the high speed or low speed of disk rotation.
In a disk drive apparatus in accordance with the present invention, the above-mentioned ring-shaped tracks may be plural in number.
Therefore, in accordance with the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk.
A balancer for a disk drive apparatus in accordance with the present invention has a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
A balancer for a disk drive apparatus in accordance with the present invention from another point of view has division means for dividing a ring-shaped track into plural tracks, arc-shaped tracks formed by the above-mentioned division means and balance members provided so as to be movable on the above-mentioned arc-shaped tracks.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
In a balancer for a disk drive apparatus in accordance with the present invention, the above-mentioned division means may be configured to absorb shock.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed.
In a balancer for a disk drive apparatus in accordance with the present invention, in at least portions of the above-mentioned arc-shaped tracks, the distance from the rotation axis of a disk to at least one track increases in the rotation direction of the disk.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
In a balancer for a disk drive apparatus in accordance with the present invention, the above-mentioned division means may be configured to be held so as to be rotatable with respect to the above-mentioned ring-shaped tracks.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
In a balancer for a disk drive apparatus in accordance with the present invention, the above-mentioned balance members may be formed of a magnetic material, and magnetic field generation means for magnetically attracting the above-mentioned balance members may be provided.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed regardless of the high speed or low speed of disk rotation.
In a balancer for a disk drive apparatus in accordance with the present invention, the above-mentioned balance members may be formed of a magnetic material, magnetic field generation means for magnetically attracting the above-mentioned balance members may be provided, and the connection portions between the above-mentioned division means and the above-mentioned ring-shaped tracks may be formed of curves.
Therefore, in accordance with the balancer for the disk drive apparatus of the present invention, noise caused from the balancer itself can be suppressed regardless of the high speed or low speed of disk rotation.
A clamper for a disk drive apparatus in accordance with the present invention comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks, and is configured to rotatably hold a disk mounted on a turntable.
Therefore, in accordance with the clamper for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
A spindle motor for a disk drive apparatus in accordance with the present invention comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks.
Therefore, in accordance with the spindle motor for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
A spindle motor for a disk drive apparatus in accordance with the present invention from another point of view comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks, wherein said balancer is provided so as to be rotatable integrally with a rotor.
Therefore, in accordance with the spindle motor for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
A spindle motor for a disk drive apparatus in accordance with the present invention from another point of view comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks, wherein said balancer is provided so as to be rotatable integrally with a spindle shaft.
Therefore, in accordance with the spindle motor for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
A turntable for a disk drive apparatus in accordance with the present invention comprises a balancer having a plurality of arc-shaped tracks and balance members provided so as to be movable on the above-mentioned arc-shaped tracks, wherein a disk is mounted thereon and the above-mentioned disk is supported rotatably.
Therefore, in accordance with the spindle motor for the disk drive apparatus of the present invention, the vibration of the sub-base can be suppressed securely regardless of the magnitude of the mass imbalance of the disk, whereby vibration and noise from the balancer can be suppressed.
In order to solve the above-mentioned problems, the disk drive apparatus of the present invention relates to a turntable and a clamper used as means for holding a disk and rotating it integrally; and concrete means thereof are described below.
A disk drive apparatus in accordance with the present invention comprises disk support means for supporting at least one side of the above-mentioned disk by using four or more projections, wherein the tips of the above-mentioned projections are substantially on the same plane.
Therefore, in accordance with the disk drive apparatus of the present invention, the disk can be held securely; and in the case when the disk is rotated at high speed, vibration and noise due to the imbalance, such as a face deflection, of the disk can be reduced, whereby it is possible to attain a disk drive apparatus capable of carrying out high-rate data transfer.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable on which a disk is mounted; and
a clamper having four or more projections, the tips of which are substantially on the same plane, wherein the above-mentioned disk is held between the above-mentioned projections and the above-mentioned turntable.
Therefore, in accordance with the disk drive apparatus of the present invention, the disk can be held securely by using the clamper; and in the case when the disk is rotated at high speed, vibration and noise due to the imbalance, such as a face deflection, of the disk can be reduced, whereby stable recording/reproduction can be attained, and it is possible to attain a disk drive apparatus capable of carrying out high-rate data transfer.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable for supporting a disk by using four or more projections, the tips of which are substantially on the same plane; and
a clamper used with the above-mentioned turntable to hold the above-mentioned disk therebetween.
Therefore, in accordance with the disk drive apparatus of the present invention, the disk can be held securely by using the turntable, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable for supporting a disk by using four or more projections, the tips of which are substantially on the same plane; and
a clamper having four or more projections and holding the above-mentioned disk between the projections and the projections of the above-mentioned turntable.
Therefore, in accordance with the disk drive apparatus of the present invention, the disk can be held securely between the turntable and the clamper, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
In the disk drive apparatus of the present invention, in addition to the means of the above-mentioned disk drive apparatus, the projections of the above-mentioned turntable and the projections of the above-mentioned clamper may be provided so as to be opposite to each other.
Therefore, in accordance with the disk drive apparatus of the present invention, the disk can be held more securely between the turntable and the clamper, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
A disk drive apparatus of the present invention, in addition to the means of the above-mentioned disk drive apparatus, may comprise:
a sub-base to which a disk rotation drive motor is secured;
a main base over which the above-mentioned sub-base is installed via elastic bodies; and
a balancer having a ring-shaped track portion accommodating plural spherical bodies therein and provided so as to be rotatable integrally with a disk.
Therefore, in accordance with the disk drive apparatus of the present invention, the balls of the balancer can be stabilized, whereby imbalance due to the eccentricity of the disk at the time of rotation can be reduced securely.
In the disk drive apparatus of the present invention, the above-mentioned projections may be disposed on a circumference being coaxial with the rotation center of a disk.
In the disk drive apparatus of the present invention, the above-mentioned projections may be disposed on circumferences having different diameters and being coaxial with the rotation center of a disk.
Therefore, in accordance with the disk drive apparatus of the present invention, vibration and noise in the case when the disk being held is rotated at high speed can be reduced further.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable provided with an elastic body on a face thereof on which a disk used as a recording medium is mounted; and
a clamper having four or more projections, the tips of which are substantially on the same plane, and holding the above-mentioned disk between the above-mentioned projections and the above-mentioned turntable.
Therefore, in accordance with the disk drive apparatus of the present invention, the unevenness on the disk mounting face of the turntable can be improved easily, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable for supporting a disk by using four or more projections, the tips of which are substantially on the same plane; and
a clamper provided with an elastic body on a face thereof for holding the above-mentioned disk to hold the above-mentioned disk between the above-mentioned elastic body and the above-mentioned turntable.
Therefore, in accordance with the disk drive apparatus of the present invention, the unevenness on the disk holding face of the clamper can be improved easily, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
A disk drive apparatus in accordance with the present invention from another point of view comprises:
a turntable provided with an elastic body on a face thereof on which a disk used as a recording medium is mounted; and
a clamper provided with an elastic body on a face thereof for holding the above-mentioned disk to hold the above-mentioned disk between the above-mentioned elastic body and the above-mentioned turntable.
Therefore, in accordance with the disk drive apparatus of the present invention, the unevenness on the disk mounting face of the turntable and the disk holding face of the clamper can be improved easily, and vibration and noise in the case when the disk is rotated at high speed can be reduced.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and content, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.